Well Design & Construction Causal Factors of the Deepwater Horizon Accident
In an earlier posting, we laid out the Causal Factors immediately before the well blowout as described by Terry Barr.
Now someone else has helped us identify the Causal Factors associated with the well design and construction. The Committee on Energy and Commerce investigation into the well blowout has identified 5 Causal Factors in a letter to Tony Hayward dated June 14, 2010. That letter is also covered in a Wall Street Journal article.
I’ll summarize the Causal Factors here and let you read the details in the letter liked to above.
Well Design and Construction Causal Factors
- Choice of the cheaper, but less safe, well completion liner option to complete the well.
- Using to few casing centralizers for the well design.
- Failure to perform a cement bond log.
- Failure to circulate the mud prior to cementing per the API standard.
- Failure to deploy the casing hanger lockdown sleeve prior to replacing the mud with seawater.
That makes a total of 12 Causal Factors for the incident BEFORE the blowout preventer failed.
The blowout preventer failure will have one or more Causal Factors and the failures to contain and cleanup the spill and minimize environmental damage will have multiple Causal Factors. Of course, the multiple number of failures is “normal” in an accident of this significance. And when all these Causal Factors are analyzed for their root causes, there will be a significant number of ways that BP, and perhaps the industry, can learn from this accident and improve performance so that we don’t have to kill 11 workers and cause an environmental nightmare ever again.
One last note … All the Causal Factors mentioned here are based on publicly available information. We haven’t done any interviews or collected any first-hand information. It would be nice to see a fully qualified investigative team use advanced tools to perform a real root cause analysis on the first-hand data.
Also, I have posted the Congressional Letter below to make sure that it is available to those reviewing this article in the future…